Tuesday, June 3, 2014

WNTV Blog: Severe and Heavy Rain Threats Continue


Lake Levels Running High
I snapped this picture Tuesday morning of Lake Minnetonka in Excelsior, MN. It is apparent that lake levels are running quite high from the recent heavy rain event from last weekend!!




Summer Solstice
The Summer Solstice arrives on Saturday, June 21st at 5:51am CDT



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Stormy Outlook Ahead
Look at the vigorous area of low pressure scooting through the central U.S.. This will be responsible for an ongoing severe weather threat through the 2nd half of the week and it tracks east. Not only will there be a severe weather threat, but a flood threat could be possible in areas that see heavy rains from convective precipitation.



Severe Threat Wednesday
 
...SUMMARY... STRONG TO SEVERE STORMS WILL BE POSSIBLE FROM PARTS OF THE SOUTHERN PLAINS AND NWD INTO THE CENTRAL HIGH PLAINS AS WELL AS FARTHER EAST INTO SOUTHEASTERN VIRGINIA AND EASTERN NORTH CAROLINA. ISOLATED DAMAGING WIND AND LARGE HAIL WILL BE THE MAIN THREATS. ...SYNOPSIS... THE LOW AMPLITUDE...PROGRESSIVE SHORTWAVE TROUGH WILL MOVE OFF THE ATLANTIC SEABOARD EARLY THURSDAY...BUT A BROAD SYNOPTIC UPPER TROUGH WILL REMAIN OVER THE ERN STATES. FARTHER UPSTREAM A ZONAL PATTERN WILL PERSIST FROM THE WEST COAST EWD THROUGH THE PLAINS AND MS VALLEY REGIONS. SEVERAL LOW AMPLITUDE SHORTWAVE TROUGHS WILL MOVE THROUGH THIS FLOW REGIME. AT THE SFC A COLD FRONT WILL MOVE OFF THE ATLANTIC SEABOARD IN ASSOCIATION WITH THE EXITING SHORTWAVE TROUGH. TRAILING PORTION OF THIS BOUNDARY WILL LIKELY STALL FROM OK EWD INTO THE LOWER MS VALLEY REGION. FARTHER NORTH A COLD FRONT IS FORECAST TO MOVE THROUGH THE NRN PLAINS AREA.



Severe Threat Thursday

...SUMMARY... STRONG TO SEVERE STORMS WILL BE POSSIBLE FROM PARTS OF THE SOUTHERN PLAINS AND NWD INTO THE CENTRAL HIGH PLAINS AS WELL AS FARTHER EAST INTO SOUTHEASTERN VIRGINIA AND EASTERN NORTH CAROLINA. ISOLATED DAMAGING WIND AND LARGE HAIL WILL BE THE MAIN THREATS. ...SYNOPSIS... THE LOW AMPLITUDE...PROGRESSIVE SHORTWAVE TROUGH WILL MOVE OFF THE ATLANTIC SEABOARD EARLY THURSDAY...BUT A BROAD SYNOPTIC UPPER TROUGH WILL REMAIN OVER THE ERN STATES. FARTHER UPSTREAM A ZONAL PATTERN WILL PERSIST FROM THE WEST COAST EWD THROUGH THE PLAINS AND MS VALLEY REGIONS. SEVERAL LOW AMPLITUDE SHORTWAVE TROUGHS WILL MOVE THROUGH THIS FLOW REGIME. AT THE SFC A COLD FRONT WILL MOVE OFF THE ATLANTIC SEABOARD IN ASSOCIATION WITH THE EXITING SHORTWAVE TROUGH. TRAILING PORTION OF THIS BOUNDARY WILL LIKELY STALL FROM OK EWD INTO THE LOWER MS VALLEY REGION. FARTHER NORTH A COLD FRONT IS FORECAST TO MOVE THROUGH THE NRN PLAINS AREA.



Heavy Rain Threat
Another big concern will be the heavy rain over sections of the central U.S.. According to NOAA's HPC, the 5 day precipitation forecast (from AM Tuesday - AM Sunday) suggests nearly 5"+ over the nation's heartland. Most of this rainfall will occur in a short period, which may cause areas to see flash flooding.



Flash Flood Watch
Through AM Wednesday:

EXCESSIVE RAINFALL RATES WILL LEAD TO HIGH RUNOFF RATES OVERNIGHT. WIDESPREAD TOTAL PRECIPITATION AMOUNTS LOOK TO RANGE FROM 2 TO 4 INCHES BY WEDNESDAY MORNING...BUT COULD SEE ISOLATED AMOUNTS OF 5 INCHES OR GREATER. * SMALL CREEKS AND STREAMS TYPICALLY SUSCEPTIBLE TO FLASH FLOODING MAY RISE VERY RAPIDLY TONIGHT...ESPECIALLY IN URBAN AREAS.



Heat Concerns
Record heat popped up earlier this week in places like Phoenix and Tucson, AZ as temperatures soared into the triple digits. It appears that more record and near record heat will continue over the next couple of days. Thanks to my parents for the pictures below from Sun City Grande. This was the sunset after a record setting 110F in Phoenix, AZ (tied 110F set in 2013).




AN EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM MST THURSDAY. * AFFECTED AREA...THE PHOENIX METRO AREA AND SURROUNDING LOWER DESERTS INCLUDING GILA BEND...CASA GRANDE...COOLIDGE...AND OTHER NEARBY AREAS. * WARNING TIME EACH DAY...GENERALLY FROM 10 AM TO 8 PM. * TEMPERATURE...HIGHEST TEMPERATURES FROM 109-111 DEGREES. * IMPACTS...EXCEEDINGLY HIGH TEMPERATURES CAN CAUSE HEAT RELATED ILLNESS...EVEN DEATH. THOSE WORKING OR PLAYING OUTDOORS... THOSE WITHOUT AIR CONDITIONING...OR PEOPLE SENSITIVE TO HEAT WILL NEED TO TAKE PRECAUTIONS.



Tropical Update
This was the view of Tropical Storm Boris (BOR-EES) in the Eastern Pacific around midday Tuesday. Note the broad counterclockwise circulation just offshore (Mexico). This is our second named storm of the 2014 Eastern Pacific Hurricane Season. It was over Memorial Weekend that Hurricane Amanda rapidly developed into a category 4 storm, which became the strongest storm this early in the season for the Eastern Pacific.



Tracking The Tropics

DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ SATELLITE DATA INDICATE THAT THE DEPRESSION HAS STRENGTHENED INTO A TROPICAL STORM. AT 1100 AM PDT...1800 UTC...THE CENTER OF TROPICAL STORM BORIS WAS LOCATED NEAR LATITUDE 14.7 NORTH...LONGITUDE 94.1 WEST. BORIS IS MOVING TOWARD THE NORTH NEAR 5 MPH...7 KM/H...AND THIS GENERAL MOTION IS EXPECTED FOR THE NEXT COUPLE OF DAYS. ON THE FORECAST TRACK...THE CENTER OF BORIS SHOULD BE NEAR THE COAST OF MEXICO WITHIN THE WARNING AREA EARLY WEDNESDAY. MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 40 MPH...65 KM/H...WITH HIGHER GUSTS. NO SIGNIFICANT STRENGTHENING IS EXPECTED BEFORE LANDFALL. TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 80 MILES...130 KM...NORTHEAST OF THE CENTER. PUERTO CHIAPAS MEXICO HAS ALREADY REPORTED 3.78 INCHES OF RAIN FROM BORIS. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 999 MB...29.50 INCHES. HAZARDS AFFECTING LAND ---------------------- WIND...TROPICAL STORM CONDITIONS ARE REACHING THE COAST WITHIN THE WARNING AREA NOW AND SHOULD CONTINUE THROUGH TONIGHT. RAINFALL...BORIS IS EXPECTED TO PRODUCE AS MUCH AS 10 TO 20 INCHES OF RAIN OVER A LARGE PART OF SOUTHERN MEXICO THROUGH SATURDAY...WITH ISOLATED AMOUNTS EXCEEDING 30 INCHES LIKELY OVER THE MOUNTAINOUS TERRAIN OF THE MEXICAN STATES OF OAXACA AND CHIAPAS. BORIS IS ALSO EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 5 TO 10 INCHES IN GUATEMALA. THESE RAINS ARE LIKELY TO RESULT IN LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.



Here are the spaghetti models for Boris as he tracks over southern Mexico. Note that most have Boris drifting north near the Bay of Campeche



Tracking Boris
This is the GFS (American Model) outlook for Boris as he drifts north. The images below are the forecast for AM Monday and AM Wednesday of next week. Note that this particular model has Boris drifting near the Yucatan Peninsula and toward Florida! Stay tuned...

Outlook AM Monday



Outlook AM Wednesday



Thanks for checking in and have a great rest of your week ahead! Don't forget to follow me on Twitter @TNelsonWNTV